


Antimatter

by prototyping



Category: Kingdom Hearts
Genre: Action, Fights, Gen, General, KH3 fic, Swordfighting, fight fic, fight scenes are best tho, genfic, here i go again, light vs dark etc, this fandom needs more genfic
Language: English
Status: Completed
Published: 2015-01-04
Updated: 2015-01-04
Packaged: 2018-03-05 07:10:04
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,492
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3110705
Author URL: https://archiveofourown.org/users/prototyping/pseuds/prototyping
Summary: <blockquote class="userstuff">
              <p>Could he fight like this? He could manage, but he knew he wouldn't be at his best, and taking on Vanitas with anything less was dangerous. Ventus + Vanitas fight fic, circa KH3.</p>
            </blockquote>





	Antimatter

_He's here._

The thought came unbidden and sudden, snapping Ventus awake with a start. For a moment he thought someone had spoken the words out loud, but as he lay there still and listening, his eyes adjusting to the darkness as his mind caught up, he realized that the phrase had been his own, inside his head.

He sat up silently, looking around the room. Moonlight poured in through a parting in the drapes, allowing him to barely make out Terra's and Aqua's sleeping forms in the other two beds. He couldn't help a soft smile. They had all been running themselves ragged lately, so it was nice to see the other two finally catching up on some real rest, and for those times to coincide with his own. Hopefully he would be able to catch them in the morning before they headed out again. They didn't always have that luxury anymore.

The warm expression faded, however, as Ven glanced again at the window. He was certain now. He knew this feeling, this uneasy sense of foreboding and the lukewarm chill in his veins. He had felt it only once before, but it was all the more memorable for that reason. No voice could be heard, but he was certain that the sensation brought a message with it all the same, a silent will that pressed heavily on his mind and heart to get its desire across.

_Come find me._

Ven hesitated, but he already knew he couldn't leave it be. Carefully, he swung his legs over the mattress edge and stood.

A minute later he was outside the small, recently built inn, glancing either way down the path to make sure he was still alone. Waking Terra or Aqua was undoubtedly the safer choice, he knew, but he had quickly decided against it. This was his business, his fight if it came to that, and no one else needed to be dragged into it. He could handle himself fine, anyway.

He didn't need to think about where to go or worry about searching the town. The pressure on his heart directed him, tugged him, leading him between the dark buildings by instinct. Each step felt more dangerous than the last, as if he were obviously walking into a trap, but Ven kept going.

By the time he reached the gardens, that pressure had turned painful. He had a slight headache now, and inhaling made his chest feel too tight. Stopping just short of the plaza, Ven stole a glimpse over his shoulder. Contrary to its name, the new Radiant Garden was now a jumbled collection of shadows, dark windows, and sharp rooftops behind him.

_You can still go back,_ a small voice pointed out. _Get the others, or don't even go at all..._

"No," he murmured to himself. He turned ahead again, no longer needing the subconscious guidance to figure where he was wanted. "This is something I have to do."

The garden bore a striking resemblance to how he remembered it, back before its destruction: white-washed stones underfoot, a variety of colorful and healthy flowers arranged in tidy patches, and bubbling aqueducts on the edges. It was quiet out here, except for the distant sound of running water.

Too quiet.

Ven's Keyblade appeared in hand as he reached the center of the stone plaza. Its warm hilt was comforting, especially now that his headache had doubled and his limbs felt unsteady, almost weak, as if his strength were being steadily drained.

"What's wrong with me?"

No answer, although that was probably a good thing. Slowly, Ven turned in circles, searching for the reason for his being here. That reason didn't make him wait long.

The sudden spike in his senses was what warned him. He didn't see or hear a thing, but the aching discomfort clinging to every part of him seemed to suddenly focus in one place: the middle of his back.

_Behind--_

He made the experienced choice of leaping away as he turned, and fortunately so: a puddle of shadow was darting along the ground, clearly visible against the bright stones. As it reached where Ven had been standing only a second before, it erupted upward and stretched further up, up, until it was as tall as he was, a familiar Keyblade appearing in what was surely meant to be a killing arc through the air. Legs began to form in the cloud of shadow from the ground up -- feet, shins, knees -- and then hands, arms, a torso--

Ven didn't have to wait for it to finish. He knew what it was, _who_ it was, and he was already shifting into his battle stance when a pale face split the black shadows from within. Two sharp eyes, a cutting and venomous shade of yellow, filled the dark sockets and settled with unnerving, hostile intensity on Ven as soon as they had formed.

Now complete, Vanitas sneered. "Been a while, Ventus."

Ven returned the look with an icy glare, trying to ignore how sore and exhausted he felt. It was like Vanitas' appearance had made it worse. "Not long enough. What're you doing here?" he snapped. Immediately, he regretted opening his mouth: not only did his voice give him away as being tired, but something seemed to settle on his tongue and coat his throat, as if he'd directly inhaled a cloud of smoke. It felt thick and grating, tasted bitter, and swallowing only intensified both sensations.

"Heh." It was more of a grunt than a laugh. "Cutting right to the chase, as always. Sure you don't want to just skip to the part where you run at me, screaming?" When Ven didn't reply, Vanitas' grin widened and his eyes trailed down to Ven's Keyblade -- as if he could see those fingers trembling in their grip, or guess how hot and clammy Ven's palm had become. "Or is something _wrong?_ "

Ven tensed even tighter. So he _was_ doing something -- but what? This feeling, this weakness, wasn't familiar at all; Ven had trained until he nearly passed out before, but this fatigue wasn't the same. It was inside and out, as mental as it was physical, if not more so.

Could he fight like this? He could manage, but he knew he wouldn't be at his best, and taking on Vanitas with anything less was dangerous. Beyond dangerous.

But so was showing weakness. Keyblade held firm, he made a hard dash forward. "If you came here to fight, then shut up and come on!" His weapon came up and around in a horizontal slash, but Vanitas blocked it in a rather lazy-looking parry, one eyebrow raised and his amused expression a cruel satire of pity.

Even on Ven's side, the attack felt weak. About three steps away from Vanitas, the pain and weariness had managed to double again, maybe triple, this time bringing a severe wave of nausea with it and effectively sapping most of the strength from his blow. The awful taste in his mouth, the tinge of old blood, of rot, of defeat and despair and death -- it was in his nose now, too, he could smell it, it was clouding and overwhelming all of his senses and he felt his grip loosening--

"Is that it?" Vanitas chuckled, the sound made of more disgust than humor. "Off your game after your long _nap?"_ He drew back, ducked, and slammed a hard kick into Ven's gut, all too fast to follow. Ven hit his back, reflexively rolled onto his feet, and righted himself with another quick jump backwards. Instantly the cloudiness in his mind, the exhaustion in his body, eased up a little.

_It's him,_ Ven realized. _If I get close, it gets worse. So how can I--_

Vanitas blurred, appeared in front of him, and bore down with a two-handed blow. Reflex kicked in again and Keyblades clashed once, twice, three times before Ven was driven backwards a second time, but not before a fourth well-timed swing slashed across his stomach. Pain flared, but it was a shallow cut with more shock than substance.

This time Ven didn't just react, however -- he threw out a rapid (and difficult, thanks to his muddled senses) casting of Firaga, but in more distraction than offense as he used the couple seconds it bought him to switch hands and slam his fist against the steel plate on his shoulder.

He only had defense in mind, but as his armor appeared and covered him from head to toe, Ven was surprised to feel the effects of Vanitas' presence diminish significantly. His head was instantly much lighter with clarity, his body more stable, and he blocked his enemy's next swing with renewed strength and speed and purpose. He still wasn't at one hundred percent, but he would gladly take the improvement all the same.

Vanitas wasn't put off by the recovery, but put it to the test as he continued to lash out with attack after attack. Ven was pushed into remaining largely on the defensive. He tried not to think too much about the connection between Vanitas and his armor and what it could mean; he needed all of his focus on the fight at hand. As always, Vanitas was no pushover, but current handicaps notwithstanding there was something different about him -- Ven would have hazarded the guess that he was _stronger_ than last time, somehow, if his physical strength alone was anything to go by, and he dodged many of Ven's attacks with what looked like little effort. When one of his own spells connected, it was like Ven had been hit by a wall: the armor may have protected him on the outside, but it likely caused a number of bruises all the same.

His breastplate and gauntlets were soon covered in scrapes and ferocious gashes, and twice his helm was clipped hard enough to make him teeter and stumble. The savage brutality of the attacks was enough to wear him down at an alarming pace, and that wasn't even taking into account how tired he already felt. Cold sweat soaked his back and the insides of his gloves, and it was a battle in itself to try and control his labored breathing. Attacking or even healing was out of the question now. He could only put his all into parrying and dodging, and even that was decreasingly successful.

The last spell caught him off guard completely. Vanitas unleashed a blast of fire nearly point-blank, and Ven's frantic scramble against his current momentum cost him both time and balance. Unfortunately, Vanitas had intended just that and his follow-up was perfect: he darted forward, keeping low, and put his all into an uppercut that Ven's Keyblade only barely blocked. That, too, seemed planned, because Vanitas shifted instantly, wrenching hard in just the right way to finally break Ven's weakening grip.

His Keyblade went skittering across the stones and into the shadows, lost from sight. Ven felt for it with his mind, his heart, to try and summon it back to him, but the effort was disrupted by the literal shattering blow to his side. He heard the sound before he felt the impact, a horrible, piercing shriek as metal bit and tore into metal. The world tilted in slow motion as the blow knocked him off his feet, and then the pain raged across his side, over his previous wound, as vulnerable skin ripped and split much easier than his steel armor had. It felt like his body was on fire. The agony was so intense that he didn't notice Vanitas moving to catch him before he hit the ground--

\--by way of slinging his Keyblade and launching a bolt of darkness that caught Ven dead center. It sent him bouncing and skidding some way or another, his armor's plates groaning and scraping against stone and one another loud enough to deafen him, but they no doubt saved him from worse injuries. He was still bruised and battered by the time his back collided with a wall, abruptly and painfully stopping his trek, and his side was in such torment now that he could barely breathe, let alone move.

Even so, the reality of the situation wasn't lost on his reeling mind: he was going to die if he didn't do something. He needed a moment to gather his bearings, to force in some sharp, stabbing breaths, but then Ven bit down on that copper taste in his mouth and pushed himself up, shouting in agony as well as anger. It somehow helped, the raw sound of his scream in his ears, even if he knew no one besides his enemy could hear it. He managed to sit up despite every muscle seeming to resist, despite how his stomach and hip were covered in something hot and wet beneath his suit. His head was still thick and sluggish, twice as much under the pain and dizziness, but he fought it all the same, reaching out for the energy needed to cast Cure. If he could do that, retrieve his Keyblade--

He cried out again, involuntarily this time, as Vanitas suddenly planted a boot on his chest and pinned him forcefully to the wall. The ringing in his ears muffled the snide comment, but Ven caught the end of it.

"--en to quit. Guess you ended up with the cockroach tenacity between us." Keeping his foot firmly in place, Vanitas reached down, slipped two fingers under the base of Ven's helm, and then swiftly ripped it off his head. With a breath of fresh, cool air came that awful sensation again: choking, smothering, overwhelming, now even worse than before. Ven coughed, gagged, and Vanitas only tossed the helm uselessly aside before perching his free arm on his knee. "Still haven't figured it out, huh?"

Ven glared up at him, unable to answer without running the risk of retching. Vanitas cracked a cold grin and chuckled, this time sounding genuinely, sadistically pleased. "Oh, _right._ Must be pretty hard to do anything at this range." He glanced aside at his Keyblade as he held it straight up, turning it slightly in idle examination of its twisted features. "In case you haven't, I'll let you in on the joke. You might have beaten me once--"

_Twice,_ thought Ven.

"--I'll give you that. But funny thing is, turns out it's what's inside that counts." He bumped his chest with a fist as his voice lowered, managing to sound even more hateful and condescending than he was already. "You might have grown up a little and gotten stronger, but your little heart of light's as weak as it's ever been. And with the way I am now?" He placed more weight on Ven, earning a snarling cough. "Just being _around_ your better half is enough to strangle you from the inside."

His eyes were trained on Vanitas, but Ven's attention was preoccupied with pushing back the smog in his brain, which he only just managed through a blend of adrenaline and directed rage. Just enough to think.

_Darkness. It's his darkness. It's smothering my light, somehow?_

But why? Because he was stronger than before?

"It's pretty rough," Vanitas went on, "but it won't actually kill you." In the blink of an eye, he shifted his grip and redirected his Keyblade to touch its point to Ven's cheek. Some slight pressure, a piercing sting, and Ven felt warm blood trickle down his jaw. "I'll take care of that myself."

_If his darkness hurts my light, why can't it go the other way, too? Think, think! There's gotta be a way! It's always equal!_

Vanitas kicked off of Ven and straightened up. "As fascinating as this conversation is, I think it's about time I ended it."

_How can I hurt him? How?! I can't cast... and without my Keyblade..._

_Darkness and light -- my heart's weaker than his? But I destroyed both..._ Ven's thoughts fought to pick up speed, churning against the dark force that tried to weigh them down and stifle them. As Vanitas raised his Keyblade above his shoulder, Ven remained motionless, but his mind was working overtime, searching and grasping for something, anything-- _Terra -- Aqua -- what would you do? My light's not strong enough!_

As a last, desperate resort he reached out to Vanitas himself -- rather, to that smothering, despairing sensation emanating from him. Ven mentally threw himself at it, searching it, probing it, and then finally giving in to it, dropping the walls he had instinctively put up around his heart and mind to guard against it.

Time slowed to a crawl. Suddenly Ven was looking at himself -- he looked terrible, slumped over, a bloody and broken mess of wounded and twisted metal. Confused, he try to glance at something else, but he couldn't move his eyes. Then he realized that he was right where Vanitas should have been standing. Rather...

...he _was_ Vanitas.

He could feel that Keyblade in his strong hand, both pulsing with dark energy -- he could sense other things, too, and it took him an immeasurable moment to figure out what they were. Pain? Yes and no -- the sting of loneliness, of apathy, of insurmountable rage and hatred, but greater than that was a twisted feeling of something else. Ven couldn't call it happiness, because he knew happiness and this wasn't it. This was some sort of sick imitation, a spiteful, twisted sort of _glee_ in want of everything terrible. It was sadistic, an all-encompassing desire to hurt and kill and destroy, to watch everything and everyone burn simply because they existed. It easily drowned out that flicker of solitary pain; the hatred was greater, his only purpose, his one defining _everything._

This was Vanitas. Ven knew it, felt it, because for this brief space of time they were one again -- or at least, Ven could see inside him, pick up on his senses and hear his thoughts--

"Say good-bye, _Ven._ "

Ven felt his lips form the words, his voice say them--

\--and suddenly the connection was broken. He was himself again, wounded and bleeding and awaiting the deathblow, everything from his teeth to his knees aching from the darkness that infiltrated his lungs, veins, and joints. The walls were up again; his light was steeling him against the invader, and with that he had been ripped from Vanitas' mind back into his own weaker, familiar shell. But now he had the knowledge that he needed.

From the beginning of his apprenticeship with Eraqus, Ven's concentration had been on speed. He was quick by nature, and his second master had seen the potential in focusing on that attribute. Ven had kept at it since, and even the more casual training sessions with Terra and Aqua weren't ever without sharpening and honing his speed to some degree, or at least capitalizing on it. When he'd left the Land of Departure for the first time, working his agility into real-life combat had been the most natural feeling in world; he was _good_ at it.

In short, Ven was very fast. Even so, he wasn't sure whether he had ever moved as quickly as he did right then.

In one second he was sitting stricken and helpless, watching Vanitas' Keyblade begin its lethal decent -- in the next, before it had even fallen a full inch, Ven redefined _fast._ It was an impossible blur of motion, the kind of desperate speed that fed on pain and fear and weakness for fuel rather than being limited by them. It was the defining last-ditch effort, one that determined survival or death in an instant.

Chance, or fate, fell in Ven's favor.

Before so much as twitching, the first thing he did was dismiss his armor. It disappeared in an abrupt flash of light, no doubt blinding in the night at this range, and then he acted without waiting to see whether it had worked. He jumped up, the pain that roared and throbbed in his side hindering him slightly, but it also worked as a way of keeping him grounded, cutting cleanly and sharply through the darkness in his mind and clearing some of it away.

He caught Vanitas' wrist and intercepted the blow, rendering it harmless, but he was no longer playing defense. Still partially stunned by the blinding light, Vanitas' reaction was delayed -- not by much, but it was enough. He tried to jerk his arm away, but Ven held tight and let the motion drag him closer. The instant he saw the opening, he took it and aimed for the only weakness, the secret that their brief inner tethering had let him in on: his free hand darted out, his bare fingers closed tight over Vanitas' jaw. Their skins touched.

The result was immediate. Vanitas screamed, a twisted and tormented noise that, even to Ven, was more jarring than it was relieving. Confidence changed to panic. Vanitas tried to tear himself away, but Ven held tight, his short nails digging into skin to keep his grip.

"If you're really me," Ven snapped, voice hoarse but firm, "then you should know--"

In the corner of his eye he saw Vanitas' Keyblade come up in a wild swing, but too late. As Ven let go of that wrist, he held out his hand and his own Keyblade slammed into his palm, narrowly deflecting Vanitas' blow away from his throat.

"--only my friends--"

Ven's burst of strength was short-lived, so his grasping hand was knocked away rather easily when Vanitas struck hard at his elbow, but there was still an opening there and Ven took it, delivering a sharp uppercut with his blade.

"-- _call me Ven!_ "

White steel raked over Vanitas from hip to shoulder. It wasn't a deep blow, but judging by the sparks it ignited and the jagged trail of light it left behind rather than blood, it was effective. Vanitas staggered, caught himself, and then retreated a dozen paces in a quick backward leap, gripping his chest. Rather than pursuing, Ven immediately cast two rounds of Cure on himself, the most he could manage, and then slumped slightly under the effort while still staying on his feet.

Across the way, Vanitas was difficult to read right then, his face twisted in pain or anger or both. The skin around his mouth was red, and where the glow of his chest injury had faded there now oozed some kind of black smoke.

"Very good," he hissed, the words somehow coming out like an insult. "But it doesn't really look like you're up for round two, now, does it?"

Ven was panting, his shoulders sagging, but he held his Keyblade tight at his side. "You can't touch me," he breathed. "That's... it, isn't it? Your heart... affects mine now, but... if I touch you... it's the same thing..." He winced. His healing spells had only done so much, and without his armor he was once again entirely exposed to that dark aura.

"Tch. Lucky guess."

So he didn't know. He hadn't noticed Ven connecting to him a minute ago.

Vanitas resumed his battle stance, his Keyblade held overhand. "I don't have to touch you to kill you, remember? So--" again he dashed at Ven, poised for a fatal strike, "--stay still and die!"

Ven watched him approach. Every instinct of self-preservation rebelled against him then, urging him to move, but he knew it was useless. His adrenaline and emergency reserve of strength were spent and he had nothing left to give; it was all he could do just to stay upright.

_Terra... Aqua..._ His eyelids were heavy, but his eyes stayed open. He wouldn't hide from himself, even at the end. _I'm sorry._

Vanitas drew close.

_"Ven!"_

Light. Sparks. A cry.

Ven flinched and shielded his eyes, momentarily stunned. When his vision cleared, he could see a faint shimmer less than an arm's length in front of him, and it curled around to his left and right, above and below him, too. As he watched, the barrier faded and he was left staring ahead at Vanitas, who had again retreated a short distance away looking sour. Footsteps grew louder, and before Ven could gather the strength to turn and identify the sources, one appeared on each side of him with Keyblades drawn and expressions stern.

"Terra! Aqua!"

As intent as they were upon Vanitas, they didn't look over, but Terra answered. "It's okay, Ven. We'll handle it." His tone was even, but it held an underlying sense of foreboding -- a calm, deadly anger, all the more threatening for how collected he appeared.

Vanitas scoffed, bitter and snide. "How predictable. Looks like some things never change." Directly behind him, the night air flickered, warped, and then tore apart to expose a yawning portal of darkness. He took a step back. "Go ahead and run home to your babysitters," he remarked, locking eyes with Ven. "I can finish my business with you later."

"No, you don't!" Aqua bolted after him, but Vanitas beat her to it. The portal closed and vanished, taking him with it when she was still several paces away. If there was any doubt as to his departure, it vanished as Ven felt the weight lift from his heart. He could think clearly again, and the choking presence in his throat dissipated.

"He's gone," he assured the other two, barely managing above a whisper. The very last of his strength left him and he hit his knees, his Keyblade clattering to the ground and vanishing in a flash. Before he could collapse completely, Terra was there to catch and gently lower him.

"Ven -- Ven! Hey!" Terra quickly looked him over, his eyes lingering somewhere around Ven's middle and widening slightly. He hissed between his teeth, concern breaking what was left of his stoicism, and shifted his grip to place a palm over Ven's bloody chest. "Aqua!"

The stars above had already faded from Ven's darkening sight, but that was fine. He was fine, as safe as he could ever be now, and that relief flooded over him more effectively than his Cures had. A blur of color was all that indicated Aqua's return, and then he was vaguely aware of more healing spells being pressed against him, into him, the warmth of Terra's knees against his back and a cool hand on his forehead and the hum of their voices although he couldn't make out the words and his head felt light he was kind of dizzy he couldn't figure out if the pain in his side was getting better or worse but everything seemed so far away now--

But Ven knew his best friends. Even though he couldn't hear them or even see their faces now, he had an idea of what needed to be said. Right before he passed out, he managed a small, weak smile up at them both.

"Thanks... Y'guys worry too much."

Sleep took him, and this time he welcomed it gladly.


End file.
